Geometric sequencemm mm

1 3 9 27 81

I 1 3 1 32 c 1 33 1 34

first term u 1

Common ratior UuI

Ngaio

3 b 12 24 48

First term Ui 3

Common ratio r UIUI

r I

Form a geometric seq with

a First term 41 5

common ratio r 2

5 10 201 40

b 41 2 7 3

21 b 18 54 so

c UL 200 L

200 100 50 25

d Ul a r r

a ar ar ar AM ar

t T410 Un

The nth term formula for geometric

Un U yh l

On lFind the 10th term of

2 6 18 1 54 162

solutionhere u Z r 3

n IUn Ul r

lo I

410 2 3

2 39

39366

Find the qtr term of

a 12 18 27

UI 12 1,82

32

Uq 12 Zz8

307.5

b it I I I I

UI it r 48416

n I

un UI Vg

Ugt C 2

16

to16 16 16

3 The three consecutive terms of

a geometric seq are

K l 2K 21 K Findk

Solution K l 2K 21 K

ratios must be same

2

K I 2K

4K21 K

K l

4k 21K 21 K2 1K

b K2 22k 121 0

5k2 15k 7k 121 0

5k 7 K 3

JkYg k3Jthe three terms

are 216118

if k ZI 19

Find K and the 3 terms

K 14 5k 14 K 120

5 y _V2

5k 14 k 120

K 14 5k 14

5k 142 K 14 K 120

251 2 140kt lb K2 124kt 80

24142 16 K 64 0

8 3k2 12K 810 f 24

3 K2 16k 4k s4L 2

3 k C k 124 K 121 0

K 12 3k 43 0

k4kZ 3

if k 2 terms are 2 6,18

If K 5 a n 130,332 I

In a geometric seq5th term is 3 and seventh term is o 75

Find the 10th term

solutionUs 3 and Ur o 75

Ui r't 3 y6 0 75

uIUl r4 3

y O 25

rt

UI4 3

Ul Et 3

Ui Xt 3

41480 and r It

9Uto Ul XV

48 I E9

Uto 2or 4 Ulo I3

47 24 HIS 3 84 Find Un

solution

U2 24 U rb 24

U 15 384 Ul V4 384

III T8 16

r t

Ul Ifb 24

Ul x 8 24

u

Un 3 If2